Wood harvester apparatus and harvesting and wood processing method

ABSTRACT

A harvester apparatus ( 100 ) equipped in a work vehicle and capable of at least cutting down, pruning, and cross-cutting wood, the harvester apparatus being configured to include a gripping claw ( 116 ) that can hold the wood by opening and closing in the thickness direction of the wood, a chain saw ( 120 ) capable of cutting the wood held with the gripping claw ( 116 ), a pruner ( 110 ) for pruning the wood arranged at a different position in the lengthwise direction of the gripped wood relative to the gripping claw ( 116 ), a slide frame ( 105 ) that can change the lengthwise distance between the pruner ( 110 ) and the gripping claw ( 116 ), and a sensor ( 130 ) for detecting the slide amount of the slide frame ( 105 ).

TECHNICAL FIELD

The present invention relates to the technical field of harvesterapparatuses that are equipped in work vehicles and capable of at leastcutting down, pruning, and cutting wood.

BACKGROUND ART

The wood processor apparatus 20 shown in FIG. 12 and FIG. 13 has beenknown in the past (see Japanese Patent Laid-Open Publication No.2005-27509).

This processor apparatus 20 is attached to the distal end of a movablearm 14 of a work vehicle 10 such as a power shovel and used as shown inFIG. 12. The processor apparatus 20 includes a gripper 22 capable ofholding a piece of wood W that has already been cut down, a feeder 24for feeding the wood W held by this gripper 22 in a lengthwisedirection, a cutter 26 capable of cutting the wood W at a predeterminedposition, and a pruner 23 for pruning off branches from the wood W. Thepruning with this pruner 23 is achieved by feeding out the wood W in thelengthwise direction by the feeder 24.

With the use of such a processor apparatus 20, wood processing such aspruning, cross-cutting and the like as well as wood transportation canbe achieved with only one apparatus (work vehicle), enabling theseoperations to be done in understaffed situations.

However, since the above-described processor apparatus 20 is not capableof cutting down trees growing on the ground (hereinafter referred to as“live trees”), it is necessary to cut down live trees first using othermeans such as saws or chain saws before performing the wood processingwith this processor apparatus 20.

Another issue is with the feeder 24, in which the wood is fed in thelengthwise direction by, for example, driving a toothed wheel or acrawler that is in contact with the surface of the wood. An inevitableconsequence of such a feeder 24 design is slippage on the wood surface.This results in more time spent for feeding the Wood and reduced workefficiency. On the contrary, if the contact pressure Of the toothedwheel or crawler against the wood is increased to avoid this situation,the wood will be much damaged at the contact points, which may lower itsvalue as a wood material.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide a harvesterapparatus capable of cutting down live trees as well as feeding the woodin the lengthwise direction swiftly and freely without the help of atoothed wheel or a crawler.

The present invention is a harvester apparatus equipped in a workvehicle and capable of at least cutting down, pruning, and cross-cuttingwood, including: a gripper that can hold the wood by opening and closingin a thickness direction of the wood; a cutter capable of cutting thewood held with the gripper; a pruner for pruning the wood arranged at adifferent position in a lengthwise direction of the gripped woodrelative to the gripper; a slide mechanism that can change a distance ina lengthwise direction between the pruner and the gripper; and a sensorfor detecting a slide amount of the slide portion. This achieves theabove object.

By adopting this structure, it is possible to make the gripper slidealong the length of the wood relative to the pruner, with the gripperholding the wood. That is, the wood can be slid (fed) relative to thepruner. According to the present invention, the is wood is not slid witha toothed wheel or a crawler in contact with the wood, and thereforethere is no problem of slippage occurring at the interface with thewood, and the wood can be slid fast. Also there is no problem of severedamage to the wood. Furthermore, because the slide amount of the slidemechanism is detected by the detection sensor, the slide mechanism canbe slid freely by a desired amount.

More specifically, for example, the pruner may be configured to includea stationary knife secured to the apparatus main body and a movableknife supported on the apparatus main body and capable of holding thewood by opening and closing in the thickness direction of the wood, andwith the wood held at two points with this movable knife and thegripper, the slide mechanism is driven, with the grip of the gripperbeing adjusted at a predetermined timing, as a result of which it ismade possible to slide (feed) the gripped wood fast in the lengthwisedirection relative to the pruner.

The present invention can also be interpreted as a wood processingmethod using a harvester apparatus that is equipped in a work vehicleand capable of at least cutting down, pruning, and cross-cutting wood,characterized by having steps of opening both of a gripper and a movableknife, the gripper being capable of holding the wood by opening andclosing in the thickness direction of the wood, and the movable knifebeing a part of a pruner arranged at a different position in thelengthwise direction of the gripped wood relative to the gripper andcapable of opening and closing in the thickness direction of the wood;closing the gripper and the movable knife after enclosing the woodinside the open gripper and the movable knife; cutting the gripped wood;increasing the lengthwise distance between the gripper and the movableknife with the gripper holding the wood and with the movable knife beingclosed; and decreasing the lengthwise distance between the gripper andthe movable knife with the grip on the wood of the gripper being reducedand with the movable knife being closed.

The “lengthwise direction” and the “thickness direction” in thedescription of the present invention refer to the respective directionsof a piece of wood that is held by the harvester apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a first perspective view of one embodiment of the harvesterapparatus 100 of the present invention;

FIG. 2 is a second perspective view of the harvester apparatus

FIG. 3 is a bottom view of the harvester apparatus 100 (taken from thedirection of arrow III in FIG. 1);

FIG. 4 is a side view of the harvester apparatus 100;

FIG. 5 is a schematic cross sectional view of the structure of thedetection sensor;

FIG. 6 is a diagram illustrating a wood processing operation with theharvester apparatus 100 before the operation is started;

FIG. 7 is a diagram illustrating the harvester apparatus 100 holding alive tree;

FIG. 8 is a diagram illustrating the moment when the live tree has beencut down with the harvester apparatus 100;

FIG. 9 is a diagram illustrating the harvester apparatus 100 that hasbegun pruning;

FIG. 10 is a diagram illustrating the pruning operation with theharvester apparatus 100 with its slide mechanism being extended;

FIG. 11 is a diagram illustrating the pruning operation with theharvester apparatus 100 with its slide mechanism that has been extendedbeing retracted again;

FIG. 12 is a schematic overall view of a work vehicle equipped with theprocessor apparatus described in Japanese Patent Laid-Open PublicationNo. 2005-27509; and

FIG. 13 is a side view of the processor apparatus described in JapanesePatent Laid-Open Publication No. 2005-27509.

BEST MODE FOR CARRYING OUT THE INVENTION

One embodiment of the present invention will be hereinafter described indetail with reference to the accompanying drawings.

FIG. 1 is a perspective view of one embodiment of the harvesterapparatus 100 of the present invention. FIG. 2 is a perspective view ofthe harvester apparatus 100 taken from another view. FIG. 3 is a bottomview of the harvester apparatus 100 (taken from the direction of arrowIII in FIG. 1). FIG. 4 is a side view of the harvester apparatus 100. Itshould be noted that the wood itself is not shown in FIG. 1 through FIG.4 for ease of description. The harvester apparatus 100 shown in FIG. 1can, for example, hold a piece of wood with its length along the up anddown direction of the drawing.

This harvester apparatus 100 is equipped in a work vehicle such as apower shovel and used, as with the example shown in the description ofconventional techniques. Not to mention, the work vehicle is not limitedto power shovels, and the apparatus can be applicable to various otherwork vehicles commonly used in construction sites such as back hoes,trucks equipped with movable arms, and so on.

The harvester apparatus 100 is configured to include a pruner 110 havinga stationary knife 111 and a movable knife 112, a gripping claw(gripper) 116 that can hold the wood by opening and closing in thethickness direction of the wood, a chain saw (cutter) 120 capable ofcutting the wood held with the gripping claw 116 to a desired length,and a slide mechanism (not shown in FIG. 1) that can change the distancebetween the pruner 110 and the gripping claw 116 (lengthwise distance Lshown in FIG. 1 of the gripped wood).

The main body 102 of the harvester apparatus 100 has a substantiallyrectangular shape. FIG. 1 illustrates the apparatus with its length (orthe length of the wood) along the up and down direction of the figure.The main body 102 accommodates a hydraulic device or the like (notshown) for controlling various portions that will be described below. Acover 103 is attached to the main body 102 to protect this hydraulicdevice or the like. A linkage portion 104 is attached to a side face ofthe main body 102. Furthermore, an attitude control cylinder 108 iscoupled to control the attitude of the main body 102 relative to thelinkage portion 104. The linkage portion 104 is coupled and secured tothe distal end of a movable arm of, for example, a power shovel, or thelike. The pruner 110, the gripping claw (gripper) 116, and the chain saw(cutter) 120 are all arranged on the opposite side to the cover 103 ofthe main body 102.

The stationary knife 111 that is part of the pruner 110 is secured toone end in the lengthwise direction of the main body 102. The movableknife 112 is supported on the main body 102 and capable of opening andclosing (in the thickness direction of the wood that is held by thegripping claw 116). Therefore, the movable knife 112 itself can grip thewood (only to an extent that it does not drop the wood, its grippingcapability not as strong as that of the gripping claw 116 that is to bedescribed later). Although not shown, the main body 102 contains insidea power source (such as a cylinder or the like) for driving the movableknife 112.

The movable knife 112 is made up of a first movable knife 112A and asecond movable knife 112B having a shape that can conform to the contourof the wood (i.e., substantially crescent), and these first movableknife 112A and second movable knife 112B are disposed substantially inmirror image arrangement. Further, the first and second movable knives112A and 112B are slightly offset from each other in the lengthwisedirection of the wood. Accordingly, when the first and second movableknives 112A and 1123 are closed, their tips do not meet but cross eachother so that they can close further toward each other. In other words,even if the wood is thin, the movable knife 112, when closed, can hold(make contact with) the wood.

The gripping claw 116 is arranged at a different position from theabove-described pruner 110 (stationary knife 111 and movable knife 112)in the lengthwise direction of the wood (up and down direction in FIG.1). That is, it is disposed at the other end in the lengthwise directionof the main body 102 relative to the pruner 110. The gripping claw 116is made up of a pair of gripping claws 116 (first gripping claw 116A andsecond gripping claw 116B) that can open and close in the thicknessdirection of the wood. Each of the first and second gripping claws 116Aand 1163 mainly consists of two plate-like members having a shape thatcan conform to the contour of the wood (i.e., substantially crescent).The distance H1 in the lengthwise direction (see FIG. 1) between the twoplate-like members forming the second gripping claw 116B is designedlarger than the distance H2 in the lengthwise direction (see FIG. 1)between the two plate-like members forming the first gripping claw 116A.Accordingly, when the first and second gripping claws 116A and 116B areclosed, their tips do not meet but cross each other so that they canclose further toward each other. In other words, even if the wood isthin, the gripping claw 116, when closed, can hold the wood, and theycan hold wood of various thicknesses by changing their opening degree.

Adjacent (or below in FIG. 1) the gripping claw 116 is provided thechain saw (cutter) 120 capable of cutting the wood held by the grippingclaw 116. The chain saw 120 is driven by a chain saw motor 122. Thechain saw 120 is normally accommodated inside a chain saw cover 124 sothat it does not get in the way of the gripped wood, but can rotatearound a fulcrum 121 when cutting the wood (see FIG. 3). Although notshown, a wood diameter sensor for measuring the diameter (thickness) ofthe gripped wood is provided near the chain saw 120.

Roller 114 can swing in the direction of the arrow K1. This roller 114functions as a length measuring device for measuring the length of thewood. By controlling this roller to be firmly pressed in the directionK1, it is possible to give it a function of pressing the wood gripped inthe gripping claw 116 toward the direction of the arrow K2. With thisfeature, the gripped wood is prevented from rattling inside the claws.

inside the main body 102 is accommodated a slide frame (slide mechanism)105 that can slide in the lengthwise direction of the main body 102(i.e., along the length of the gripped wood). The gripping claw 116, thechain saw 120, and the roller 114 described above are disposed on theside of this slide frame 105. Accordingly, the lengthwise distance (ofthe wood) between the pruner 110 and the gripping claw 116 can be freelychanged by sliding the slide frame 105. Although not shown, the slideframe 105 is driven by a power source (e.g., hydraulic cylinder or thelike) provided inside the main body 102 so that it can extend andretract swiftly.

Furthermore, a sensor (detection sensor) 130 is provided in the mainbody 102 to detect the slide amount of the slide frame 105 relative tothe main body 102 (see FIG. 5). In this embodiment, this sensor 130 issecured to the main body 102 using a seat 132. Furthermore, as shown inFIG. 5, the slide frame 105 is provided at spaced intervals withprotrusions 133 in the lengthwise direction (along its length).Therefore, the slide amount of the slide frame 105 can be determined bycounting the number of the protrusions 133. The detection sensor isobviously not limited to this type and various other designs can beadopted, such as the sensor that uses a photo diode, or the one thatdetects changes in magnetic force of a magnet embedded in the slideframe 105 using a magnetic sensor or the like to consequently determinethe slide amount of the slide frame 105. The detected information can betransmitted to a control unit (not shown) through a sensor cable 134.

Reference numeral 170 shown in FIG. 3 and FIG. 4 denotes a cable,required for operating this harvester apparatus 100 from the workvehicle such as a power shovel or the like.

Next, how to use this harvester apparatus 100 (method of processingwood) is described with reference to FIG. 6 to FIG. 11.

FIG. 6 illustrates a state before the wood processing operation isstarted, in which the harvester apparatus 100 is just about to beattached to a piece of wood (live wood) W. Using the attitude controlcylinder 108, the attitude of the harvester apparatus 100 is adjusted sothat the lengthwise direction of the main body 102 is along the length(up and down direction in FIG. 6) of the wood W.

Successively, as shown in FIG. 7, with the movable knife 112 and thegripping claw 116 being open (in the widthwise direction of the wood W),the apparatus is positioned so that the wood W is enclosed inside themovable knife 112 and the gripping claw 116. The positioning is mainlyachieved by the work vehicle X such as a power shovel or the like inwhich the harvester apparatus 100 is equipped.

Successively, the gripping claw 116 is closed. The movable knife 112 isalso closed at this time to prepare to be able to hold and support thewood W after it is cut down.

Next, as shown in FIG. 8, with the wood W being held, the chain saw 120is driven to cut the wood W. Accordingly, the wood W, after it is cut,will be held on the harvester apparatus 100, or on the work vehicle X,being gripped by the gripping claw 116 and the movable knife 112.

After that the wood W is laid substantially horizontally on the groundas shown in FIG. 9 to proceed to the pruning. The pruning operationinvolves removal of branches B (B1, B2) of the wood W with the pruner110 (stationary knife 111 and movable knife 112).

As shown in FIG. 10, the slide frame 105 is extended while the wood W isfirmly held with the gripping claw 116 (in other words, with thegripping claw 116 holding the wood W and with the movable knife 112being closed, the lengthwise distance between the gripping claw 116 andthe movable knife 112 is increased) so as to slide the wood W in thelengthwise direction (direction of the arrow in FIG. 10). Accordingly,the wood W slides relative to the pruner 110 (stationary knife 111 andmovable knife 112) so that the branches B are chipped off. Here, thewood W may not have a uniform thickness, but by providing a sensorcapable of detecting the thickness of the wood (e.g., an image sensorusing a CCD camera or the like, or a sensor that detects reaction forcefrom the wood W acting on the movable knife 112 or the roller 114) andby using the information fed back from the sensor, the grip of themovable knife 112 may be suitably adjusted.

Successively, as shown in FIG. 11, the gripping claw 116 is loosened andthe slide frame 105 is retracted (in other words, with the gripping claw116 holding the wood W and with the movable knife 112 being closed, thelengthwise distance between the gripping claw 116 and the movable knife112 is decreased) so as to move only the lengthwise position of thegripping claw 116 closer toward the pruner 110 while the position of thewood W relative to the harvester apparatus 100 remains the same. Afterthat, the series of actions (shown in FIG. 10 and FIG. 11) are repeatedto prune off the branches of the wood W as required.

As the slide amount (movement amount) of the slide frame 105 is detectedby the sensor (detection sensor) as described above, the operator canslide the wood W to a desired position. For example, if the woodincludes many warps, the amount of each sliding movement is made smallso that the wood can be slid smoothly. On the other hand, if the wooddoes not have many warps, the slide amount is increased to speed up theoperation.

As one alternative, the wood W may be cut at a predetermined positionusing the chain saw 120 during this pruning operation. In thisembodiment, the roller (length measuring device) 114 is used fordetermining the length of the wood W to which it should be cut with thechain saw 120. Thereby, the wood can be cut (cross-cut) to a desiredlength (that is determined using the roller 114). Here, the diameter(thickness) of the wood is measured with the wood diameter sensor (notshown) so that the chain saw 120 does not rotate more than necessary.

With this harvester apparatus 100, as described above, the wood is notslid with a toothed wheel or a crawler in contact with the wood, andtherefore there is no problem of slippage occurring at the interfacewith the wood, and the wood can be slid fast. Moreover, the cuttingdown, pruning, cross-cutting, and transportation of wood can all beachieved by this single harvester apparatus 100 (work vehicle X),whereby labor cost can largely be cut down, and fairly efficientoperation is made possible.

It should be noted that with this harvester apparatus 100, data such asworkload during a certain period (e.g., a day, a week, or a month) canreadily be obtained by compiling data from the sensor 130 that detectsthe slide amount of the slide frame 105, the roller 114 that functionsas a length measuring device, and the wood diameter sensor (not shown)that measures the diameter (thickness) of the wood.

Also, if necessary, the slide amount (amount of relative movement) ofthe wood can be determined more precisely based on the data obtainedfrom the sensor 130 that detects the slide amount of the slide frame105, as well as the data obtained from the roller 114 that functions asa length measuring device. That is, since the slide amount of the slideframe 105 (integrated value of slide amount in one direction) actuallyrepresents the slide amount of the gripped wood, a more precise slideamount (amount of relative movement) of the wood can be obtained bychecking up data from both of the sensor 130 and the roller 114 and by,for example, adopting an intermediate value.

INDUSTRIAL APPLICABILITY

The use of the present invention enables a single apparatus (workvehicle) to carry out cutting down, pruning, cross-cutting, andtransportation of wood. Also, it enables the wood to be slid (movedrelative to the apparatus) in the lengthwise direction swiftly andfreely by a desired length, which enhances work efficiency.

1. A harvester apparatus equipped in a work vehicle and capable of atleast cutting down, pruning, and cross-cutting wood, the apparatuscomprising: a gripper that can hold the wood by opening and closing in athickness direction of the wood; a cutter capable of cutting the woodheld with the gripper; a pruner for pruning the wood, the pruner beingarranged at a different position in a lengthwise direction of thegripped wood relative to the gripper; a slide mechanism that can changea distance in a lengthwise direction between the pruner and the gripper;and a detection sensor for detecting a slide amount of the slidemechanism.
 2. The harvester apparatus according to claim 1, wherein thepruner is configured to include a stationary knife secured to theapparatus main body and a movable knife supported on the apparatus mainbody and capable of holding the wood by opening and closing in thethickness direction of the wood.
 3. A wood processing method using aharvester apparatus that is equipped in a work vehicle and capable of atleast cutting down, pruning, and cross-cutting wood, the methodcomprising the steps of: opening both of a gripper and a movable knife,the gripper being capable of holding the wood by opening and closing ina thickness direction of the wood, and the movable knife being a part ofa pruner arranged at a different position in a lengthwise direction ofthe gripped wood relative to the gripper and capable of opening andclosing in the thickness direction of the wood; closing the gripper andthe movable knife after enclosing the wood inside the open gripper andthe movable knife; cutting the gripped wood; increasing a lengthwisedistance between the gripper and the movable knife with the gripperholding the wood and with the movable) knife being closed; anddecreasing the lengthwise distance between the gripper and the movableknife with the grip on the wood of the gripper being reduced and withthe movable knife being closed.
 4. The wood processing method using aharvester apparatus according to claim 3, wherein, in the step ofincreasing the lengthwise distance and in the step of decreasing thelengthwise distance, either the lengthwise distance or an amount ofrelative movement between the gripper and the movable knife is detectedby a sensor.